PVC Sheet Automation

PVC Sheet is finding lot of applications and is a good substitute for wood. Pyrotech has provided to one of its customers turnkey automation solution using PLC, Drives, Panels & Sensors. Here is a brief overview of the system.

(A) Process Overview : PVC sheet manufacturing process comprises of following important sections:

  • Raw material bulk handling & mixing unit
  • Process Roller
  • Calenders
  • Cooling unit
  • Haull-offunit
  • Cutting unit
  • Inspection unit

Raw material Bulk Handling & Mixing Unit :- The raw materials are automatically weighed and added to a blender as per specific ratio. The blend is then fed to a fluxing machine which melts the ingredients (both solid & liquid raw material).
Now, compounding of material is done in continuous mixers. This mixture comes as outlet on two nips. These two nips form two layers of rough sheet. These two layers of sheets are joined at a press machine, where these sheets are widened. The sheets are then fed into two process roller to move the sheet forward.
It is then processed through calender roller which converts the rough sheet into homogeneous flat (equal thickness) sheet. This thickness can be adjusted by moving upper and bottom calender.
To make the sheet flat and bring it down to the appropriate thickness, calenders have three or more rollers, each over two feet in diameter and six feet in length. The thickness of sheet is usually between 2 to 50 thousandth of an inch thick. Now, the sheet is passed through cooling unit. After cooling, the sheet is fed to Haull off unit where dust & other particles are removed off the sheet. The sheet is moved to cutting unitremoved off the sheet. The sheet is moved to cutting unit where sheet gets cut in desired length.

(B) Pyrotech Scope : Pyrotech scope in this project was to understand the customer need for automation and suggest appropriate solutions. The scope included

  • Sheet thickness control
  • Synchronizatian of calender's roller speed with process roller, Haull off motor & cutting machine.
  • Parameter displayed on digital panel meter & SCADA.
  • Selection and supply of sensors/instruments used in system i.e. LVDT, Encoder, Panel Meters, VFD's, panel & wiring of the system.
  • Process establishment in coordination with customer.

(C) Benefit to Customer

  • Product quality improved as there is no variation of sheet thickness.
  • Cost effective solution : Approx. 60% saving as compared to imported machine.
  • User friendly system.